In this large meta- analysis including 21 trials, comparing 6 or less days and 7 or more days of antibiotic therapy some things are clear. Clinical cure was similar between the compared groups [4069 patients, RR= 0.99 (95% CI, 0.97-1.01)] irrespective of the severity of pneumonia [RR= 1.05, (95% CI, 0.96-1.14)]. Relapses were similar between short and longcourse treatment groups [1923 patients, RR= 0.67 (95% CI, 0.30-1.46)]. Short-course treatment was associated with fewer serious adverse events [1923 patients, RR= 0.73 (95% CI, 0.55-0.97)] Short-course treatment resulted in lower mortality compared to long-course treatment [2802 patients, RR= 0.52 (95% CI, 0.33-0.82)].
Another great example where cumulative results unmask treatment effect that was not identified due to low numbers. One more compelling evidence to stop therapy early in CAP.